For most of the last century, the policy toward wildfire was simple: put it out. Every fire, as fast as possible. The results were not what anyone expected. Forests that had burned lightly every decade or so, clearing the undergrowth and leaving the mature trees standing, instead accumulated fuel year after year. When those forests finally did burn, they burned hot enough to kill everything, including the trees that had survived every previous fire. Agencies now set controlled burns in the same forests they once defended, which strikes some members of the public as an admission of failure and strikes the agencies as the opposite.